The Chilean government reopened the investigation into his death in January, with new tests designed to look for protein damage caused by chemical agents, suggesting poisoning.
Forensic experts at the Universidad de Murcia found three types of protein in the remains of Neruda, a Nobel laureate, two of which could be explained by advanced prostrate cancer, said the report seen by Reuters on Thursday.
The source of the third protein was not immediately clear, but could be due to natural causes such as infection, or posthumous manipulation of the remains, the report said.
An expert panel will now examine the evidence, while a further genomic analysis is still pending.
Neruda, famed for his passionate love poems and staunch communist views, is presumed to have died of cancer days after a coup in 1973 that ushered in the brutal dictatorship of Augusto Pinochet.

Latest News from World News Desk